JP2000267440A - Developing machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a required suction by making a cooling mechanism for a developing machine partly branch, and to make the inside of the developing machine in a sucked state with an inexpensive constitution. SOLUTION: The developing machine 1 is provided with a 1st air operating means (1a, 6 and 7) for shifting the air taken from one end part of the developing machine 1 along the outside wall of a storing chamber, discharging the air through the other end part of the developing machine 1, and also, making the inside of the developing machine in the sucked state, and a 2nd air operating means(10, 1b, 11 and 1c) for sucking the air in the storing chamber by the suction work generated by the 1st air operating means, and making the air confluent with the air shifting along the outside wall of the storing chamber.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a developing machine used for an image forming apparatus such as a printer and a copying machine.

[0002]

2. Description of the Related Art In a developing machine used in an image forming apparatus such as a printer or a copying machine, the inside of the developing machine is made to have a negative pressure by utilizing a flow of air in the machine or by providing a dedicated air suction duct. This prevents the toner from scattering from the surface.

[0003]

However, when the flow of air in the machine is used, a sufficient suction amount cannot be obtained, and the negative pressure in the developing machine tends to be insufficient. In addition, when a dedicated air suction duct is provided, the number of parts and the manufacturing cost are increased, which is not preferable.

An object of the present invention is to provide a required amount of suction by branching a part of a cooling mechanism of a developing machine without providing a new suction mechanism or the like, and to reduce the inside of the developing machine with an inexpensive structure. An object of the present invention is to provide a developing machine capable of reducing the pressure.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide a developing machine having a developer accommodating chamber for accommodating a developer and a mixing and stirring means provided in the chamber for mixing and agitating the developer. The first air handling means (1a, 1a,) moves the air taken in from one end of the developing device along the outer wall of the housing chamber, discharges the air from the other end of the developing device, and brings the inside of the developing device into a negative pressure state. 6, 7) and a second step of sucking the air in the accommodation chamber by the negative pressure action generated by the first air handling means and joining the air to the air moving along the outer wall of the accommodation chamber. Air handling means (10, 1b, 1
1, 1c).

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIG. FIG. 1 is a partially sectional perspective view of the developing machine. In FIG. 1, a developer accommodating chamber 3 for accommodating a two-component developer 2 composed of, for example, a toner and a carrier is provided in a developing machine 1. The developer 2 is contained in the developer storage chamber 3.
The two auger screws 4 for mixing and stirring the toner and the carrier are rotatably supported. here,
The rotation directions of the two auger screws 4 are set to be opposite to each other, and are provided so that the developer 2 is circulated and transported in the developer accommodating chamber 3. The developer 2 is circulated and conveyed to a developing roller (not shown) provided next to the developer accommodating chamber 3 (the left side of the developer accommodating chamber 3 in FIG. 1), and a photoconductor (not shown). ) Is used for developing the electrostatic latent image formed in the above.

On the outer wall of the developer accommodating chamber 3 surrounding the auger screw 4, radiating fins 3 extending radially are provided.
a is provided. The fin 3a is covered by a bottom cover 5 provided below the developer accommodating chamber 3, and one end 5a of the bottom cover 5 is connected to a projecting piece 3b formed on an outer wall of the developer accommodating chamber 3. Thus, the space 6 is formed.

The space 6 is provided along the longitudinal direction of the developing machine 1, one end of the space 6 is connected to a suction port 1a provided at one end of a frame of the developing machine, and the other end of the space 6 is
The developing device is connected to a fan duct 7 provided at the other end of the frame.

Therefore, the air taken in from the suction port 1 a is drawn by the fan 8 provided in the fan duct 7 and flows along the space 6. By flowing air into the space 6 in this manner, the developer storage chamber 3 is cooled, and the temperature rise of the developer 2 in the developer storage chamber 3 is suppressed.

Further, in the developing machine of the present invention, a top cover 9 is provided above the auger screw 4, and a space 10 is provided between the auger screw 4 and the top cover 9. The space 10 is provided along the longitudinal direction of the developing device 1, and one end thereof is connected to an outlet 1b provided at one end of a frame of the developing device. The air once sent out of the frame of the developing device via the outlet 1b is supplied to the suction port provided at one end of the frame of the developing device by the inner surface of the sealing cover 11 attached to the side surface of the frame of the developing device. The air is guided by the suction port 1c, is fed again into the developing device from the suction port 1c, and joins the air flowing through the space 6. Here, the reason that the air from the space 10 can join the space 6 is that the space 6 is in a negative pressure state with respect to the outside air.

Reference numeral 12 denotes a filter for preventing the toner inside the developing machine 1 from being discharged outside the machine.

[0012]

According to the present invention, a necessary suction amount can be obtained by branching a part of the cooling mechanism of the developing machine without providing a new suction mechanism or the like, and the inside of the developing machine can be obtained with an inexpensive structure. And a developing machine capable of reducing the pressure of the developer.

[Brief description of the drawings]

FIG. 1 is a partially sectional perspective view of a developing machine of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Developing machine, 2 ... Developer, 3 ... Developer accommodation room, 4 ... Auger screw, 5 ... Bottom cover, 6 ... Space, 7 ... Fan duct, 8 ... Fan, 9 ... Top cover, 10 ... Space , 11 ... cover, 12 ... filter, 1a ... suction port,
1b: discharge port, 1c: suction port, 3a: fin.

Claims (2)

[Claims] An image forming apparatus comprising: a developer accommodating chamber accommodating a developer; and a mixing and stirring means provided in the chamber for mixing and agitating the developer. First air handling means for moving along the outer wall of the storage chamber to discharge the air from the other end of the developing machine and to bring the inside of the developing machine into a negative pressure state; A second air handling means for sucking air in the storage chamber by the negative pressure action and joining the air to air moving along an outer wall of the storage chamber. 2. The developing device according to claim 1, further comprising a filter means for capturing floating toner in the developing device, at a position between the housing chamber and the junction of the air.